xpr(1X)xpr(1X)NAMExpr - print an X window dump
SYNOPSISxpr [-device devtype] [-scale scale] [-height inches] [-width inches]
[-left inches] [-top inches] [-header string] [-trailer string] [-land‐
scape] [-portrait] [-plane number] [-gray] [-rv] [-compact] [-output
filename] [-append filename] [-noff] [-split n] [-psfig] [-density dpi]
[-cutoff level] [-noposition] [-gamma correction] [-render algorithm]
[-slide] [filename]
OPTIONS
Specifies the device on which the file will be printed. Currently sup‐
ported: LA100 HP LaserJet series and other monochrome PCL devices such
as ThinkJet, QuietJet, RuggedWriter, HP560 series, and HP930 series
printers LN03 HP PaintJet (color mode) HP HP PaintJet XL Color Graphics
Printer (color mode) IBM PP3812 PostScript printer
The default is PostScript. -device lw (LaserWriter) is equiva‐
lent to -device ps and is provided only for backwards compati‐
bility. Affects the size of the window on the page. The Post‐
Script, LN03, and HP printers are able to translate each bit in
a window pixel map into a grid of a specified size. For example
each bit might translate into a 3x3 grid. This would be speci‐
fied by -scale 3. By default a window is printed with the
largest scale that will fit onto the page for the specified ori‐
entation. Specifies the maximum height of the page. Specifies
the maximum width of the page. Specifies the left margin in
inches. Fractions are allowed. By default the window is cen‐
tered in the page. Specifies the top margin for the picture in
inches. Fractions are allowed. Specifies a header string to be
printed above the window. Specifies a trailer string to be
printed below the window. Forces the window to printed in land‐
scape mode. By default a window is printed such that its long‐
est side follows the long side of the paper. Specifies which
bit plane to use in an image. The default is to use the entire
image and map values into black and white based on color inten‐
sities. Uses a simple 2x2, 3x3, or 4x4 gray scale conversion on
a color image, rather than mapping to strictly black and white.
This doubles, triples, or quadruples the effective width and
height of the image. Forces the window to be printed in por‐
trait mode. By default a window is printed such that its long‐
est side follows the long side of the paper. Forces the window
to be printed in reverse video. Uses simple run-length encoding
for compact representation of windows with lots of white pixels.
Specifies an output file name. If this option is not specified,
standard output is used. Specifies a filename previously pro‐
duced by xpr to which the window is to be appended. When speci‐
fied in conjunction with -append, the window will appear on the
same page as the previous window. This option allows the user
to split a window onto several pages. This might be necessary
for very large windows that would otherwise cause the printer to
overload and print the page in an obscure manner. Suppress
translation of the PostScript picture to the center of the page.
Indicates what dot-per-inch density should be used by the HP
printer. Changes the intensity level where colors are mapped to
either black or white for monochrome output on a LaserJet
printer. The level is expressed as percentage of full bright‐
ness. Fractions are allowed. This option causes header,
trailer, and image positioning command generation to be bypassed
for LaserJet, PaintJet and PaintJet XL printers. This changes
the intensity of the colors printed by PaintJet XL printer. The
correction is a floating point value in the range 0.00 to 3.00.
Consult the operator's manual to determine the correct value for
the specific printer. This allows PaintJet XL printer to render
the image with the best quality versus performance tradeoff.
Consult the operator's manual to determine which algorithms are
available. This option allows overhead transparencies to be
printed using the PaintJet and PaintJet XL printers.
DESCRIPTION
The xpr command takes as input a window dump file produced by xwd(1X)
and formats it for output on PostScript printers, the LN03 or LA100,
the IBM PP3812 page printer, the HP LaserJet (or other PCL printers),
or the HP PaintJet. If no file argument is given, the standard input
is used. By default, xpr prints the largest possible representation of
the window on the output page. Options allow the user to add headers
and trailers, specify margins, adjust the scale and orientation, and
append multiple window dumps to a single output file. Output is to
standard output unless -output is specified.
LIMITATIONS
The current version of xpr can generally print out on the LN03 most X
windows that are not larger than two-thirds of the screen. For exam‐
ple, it will be able to print out a large Emacs window, but it will
usually fail when trying to print out the entire screen. The LN03 has
memory limitations that can cause it to incorrectly print very large or
complex windows. The two most common errors encountered are “band too
complex” and “page memory exceeded.” In the first case, a window may
have a particular six pixel row that contains too many changes (from
black to white to black). This will cause the printer to drop part of
the line and possibly parts of the rest of the page. The printer will
flash the number `1' on its front panel when this problem occurs. A
possible solution to this problem is to increase the scale of the pic‐
ture, or to split the picture onto two or more pages. The second prob‐
lem, “page memory exceeded,” will occur if the picture contains too
much black, or if the picture contains complex half-tones such as the
background color of a display. When this problem occurs the printer
will automatically split the picture into two or more pages. It may
flash the number `5' on its from panel. There is no easy solution to
this problem. It will probably be necessary to either cut and paste, or
to rework the application to produce a less complex picture.
There are several limitations on the LA100 support: the picture will
always be printed in portrait mode, there is no scaling, and the aspect
ratio will be slightly off.
Support for PostScript output currently cannot handle the -append,
-noff or -split options.
The -compact option is only supported for PostScript output. It com‐
presses white space but not black space, so it is not useful for
reverse-video windows.
For color images, should map directly to PostScript image support.
HP PRINTERS
If no -density is specified on the command line 300 dots per inch will
be assumed for ljet and 90 dots per inch for pjet. Allowable density
values for a LaserJet printer are 300, 150, 100, and 75 dots per inch.
Consult the operator's manual to determine densities supported by other
printers.
If no -scale is specified the image will be expanded to fit the print‐
able page area.
The default printable page area is 8x10.5 inches. Other paper sizes can
be accommodated using the -height and -width options.
Note that a 1024x768 image fits the default printable area when pro‐
cessed at 100 dpi with scale=1, the same image can also be printed
using 300 dpi with scale=3 but will require considerably more data be
transferred to the printer.
xpr may be tailored for use with monochrome PCL printers other than the
LaserJet. To print on a ThinkJet (HP225A) xpr could be invoked as:
xpr-density 96 -width 6.667 filename
or for black-and-white output to a PaintJet:
xpr-density 180 filename
The monochrome intensity of a pixel is computed as 0.30*R + 0.59*G +
0.11*B. If a pixel's computed intensity is less than the -cutoff level
it will print as white. This maps light-on-dark display images to
black-on-white hardcopy. The default cutoff intensity is 50% of full
brightness. Example: specifying -cutoff 87.5 moves the white/black
intensity point to 87.5% of full brightness.
A LaserJet printer must be configured with sufficient memory to handle
the image. For a full page at 300 dots per inch approximately 2MB of
printer memory is required.
Color images are produced on the PaintJet at 90 dots per inch. The
PaintJet is limited to sixteen colors from its 330 color palette on
each horizontal print line. xpr will issue a warning message if more
than sixteen colors are encountered on a line. xpr will program the
PaintJet for the first sixteen colors encountered on each line and use
the nearest matching programmed value for other colors present on the
line.
Specifying the -rv, reverse video, option for the PaintJet will cause
black and white to be interchanged on the output image. No other col‐
ors are changed.
Multiplane images must be recorded by xwd in ZPixmap format. Single
plane (monochrome) images may be in either XYPixmap or ZPixmap format.
Some PCL printers do not recognize image positioning commands. Output
for these printers will not be centered on the page and header and
trailer strings may not appear where expected.
The -gamma and -render options are supported only on the PaintJet XL
printers.
The -slide option is not supported for LaserJet printers.
The -split option is not supported for HP printers.
The -gray option is not supported for HP or IBM printers.
Copyright 1986, Marvin Solomon and the University of Wisconsin. Copy‐
right 1988, Hewlett Packard Company.
See X(1X) for a full statement of rights and permissions.
SEE ALSOxwd(1X), xwud(1X), X(1X)AUTHORS
Michael R. Gretzinger, MIT Project Athena, Jose Capo, MIT Project
Athena (PP3812 support), Marvin Solomon, University of Wisconsin, Bob
Scheifler, MIT, Angela Bock and E. Mike Durbin, Rich Inc. (grayscale),
Larry Rupp, HP (HP printer support).
xpr(1X)
